Conventionally, for example, in Japanese Unexamined Patent Application Publication No. 2010-260378, a pneumatic tire is described in which a plurality of ridges (projections) extending in the tire radial direction is provided at predetermined intervals in the tire circumferential direction on the tire side section (tire side surface) on the inner side in the vehicle width direction when mounted on a vehicle, and a plurality of recesses is provided over the tire circumferential direction and the tire radial direction on the tire side section that corresponds to the outer side in the vehicle width direction when mounted on a vehicle. When mounted on a vehicle, air flows uniformly toward the rear on the outer side in the vehicle width direction, but on the inner side in the vehicle width direction, the tire is disposed within the tire house, and other components such as the axle and the like are disposed nearby, so the flow of the air is easily disturbed. According to this pneumatic tire, an air flow distribution promotion effect and straightening effect are obtained and the air resistance is reduced by the ridges provided on the tire side section on the inner side in the vehicle width direction of the vehicle where the air flow is easily disturbed, and turbulent flow at the periphery of the tire is produced when the vehicle is traveling by the recesses provided on the tire side section on the outer side in the vehicle width direction of the vehicle, and drag that tends to pull the tire backward due to the low pressure portion produced to the rear of the tire when traveling is reduced, so the fuel economy is improved.
According to the technology of Japanese Unexamined Patent Application Publication No. 2010-260378, the air flow around the tire when the vehicle is traveling is improved by the ridges and recesses provided in the pneumatic tire. However, the pneumatic tires are disposed within the tire house of the vehicle, so the inventors have discovered that there is also scope for improvement at the tire house side.